Biomedical subjects

M Yamaguchi

Publications and source records attributed to M Yamaguchi.

At least 1,297 records · Page 72Linked to original sources

PubMed1990

The protein synthesis of human full term placenta cell in monolayer culture system.

Protein synthesis of human placenta from cesarean section was analyzed by SDS gel electrophoresis using full term cell culture system. The qualitative pattern of cytoskeletal proteins before and after culture was also examined. After trypsinization, cytotrophoblasts were cultured for 20 days in the humidified incubator of 5% CO2 in 95% air. The confluency was obtained in 10 days after inoculation. The pattern of SDS-PAGE showed several protein bands including actin (43,000 Da) and desmin (55,000 Da) as major constituents of 12 and 20 day cultures. The significant differences between band appearances in samples before and after culturing were noted. The present results indicated that myosin may not be synthesized in high content, differing from previous observations. Cytoskeletal protein production seemed to be markedly enhanced in the cultured system.

Actins↗

PubMed1990

Ca2(+)-insensitive contraction in glycerinated skeletal muscle fiber treated with additional troponin T.

An investigation was carried out on the effect of troponin T (TnT) protein on the Ca2(+)-sensitivity of fiber contraction when it was added to glycerinated muscle fiber. The TnT-treated fiber was observed to lose its Ca2(+)-sensitivity, so that it was seen to contract even in a Ca2(+)-free buffer solution. However, the treated fibers were not significantly different from the normally glycerinated ones in terms of tension magnitude. On the other hand, the fiber did not lose its Ca2(+)-sensitivity upon treatment in a similar manner with troponin I (TnI) or troponin C (TnC) protein instead of TnT; the tension magnitude was seen to decrease only with the TnI treatment. SDS-PAGE patterns of the TnT-treated fibers were different from those of glycerinated ones at the TnI and TnC band, which were fainter in the TnT-treated fibers than in the normal ones. DACM-labeled fibers also decreased in the DACM-labeled TnI and TnC proteins on gel as a result of the treatment with TnT protein. Further, those proteins were completely removed from fibers into extra medium. These findings suggest either that the additional TnT protein removes TnI and TnC subunits from the troponin (Tn) complex combined with thin filaments in the fibers, or that it exchanges the total Tn complex on the thin filaments.

Animals↗

PubMed1990

[Measurement of blood flow in human tympanic membrane with spectrophotometry and laser speckle flow meter].

The purpose of this study is to evaluate the blood volume and blood flow in human tympanic membrane. Hemoglobin concentration (IHb) and oxygen saturation of hemoglobin (ISO2) were measured in 71 ears by using a tissue spectrum analyzer. Blood flow (Flow level) was measured in 40 ears by using a laser speckle flow meter. By using two fiber optic probes, these three parameters were measured in the tense part of the tympanic membrane. A comparison was made between the measurements made with fiber probe touching the tympanic membrane and the measurements not touching it. Between two measuring patterns, there was no significant differentiation in three parameters, so we took non-touching technique. IHb and Flow level had reproducibility between the first and second recordings. But ISO2 did not have clear reproducibility. In normal tympanic membrane, IHb and Flow level were not significantly correlated (r = 0.52). IHb was 16 +/- 1.3 (Mean +/- SEM) in normal cases, 17 +/- 4.6 in otitis media with effusion and 104 +/- 22.8 in acute otitis media. Flow level was 0.7 +/- 0.07 in normal cases, 0.6 +/- 0.07 in otitis media with effusion and 2.2 +/- 0.37 in acute otitis media. It is considered that the measurement of hemoglobin concentration by using tissue spectrum analyzer and the measurement of blood flow by using laser speckle flow meter are useful in the studies of the pathophysiology of human tympanic membrane.

Adolescent↗

PubMed1990

[Measurement of human laryngeal mucosal blood volume].

To the best of our knowledge little if any information is available concerning human laryngeal mucosal blood volume presumably because the larynx is an anatomical position which renders the measurement of blood flow there difficult. With the advent of a reflectance spectrophotometer, however, studies of tissue blood flow have been facilitated to a great extent. As a result, attempts have been made to determine mucosal blood volume in various organs and tissues including the gastric mucosa. Recently, an ultra-thin fiber probe (1.8 m min diameter) for measurement of tissue blood volume has been developed. Using a laryngeal flexible fiberscope attached with this newly developed probe in the opening for the forceps, an attempt was made to measure laryngeal mucosal blood volume by the method of reflectance spectrophotometry, determining IHb and ISO2 the former of which is a parameter of hemoglobin in the tissue blood vessels and the latter, a parameter of hemoglobin oxygen saturation in the tissue blood vessels. IHb of the vocal folds is significantly low, about half those of the false folds and arytenoid region, whereas ISO2 is significantly higher in the false folds and arytenoid region than in the vocal folds. The hemodynamics in the vocal folds as a high-speed vibrator are specific, unlike in other laryngeal regions. We have plans to determine laryngeal tissue blood volume at more sites so as to investigate the laryngeal tissue distribution of blood volume in greater detail. Furthermore, tissue blood volume in morbid conditions will also be determined for information which will be of value in clinical applications.

Adult↗

PubMed1990

The mode of antifungal action of (S)2-amino-4-oxo-5-hydroxypentanoic acid, RI-331.

An antifungal amino acid antibiotic, (S)2-amino-4-oxo-5-hydroxypentanoic acid (RI-331) isolated from Streptomyces sp., inhibited the biosynthesis of protein to a greater extent than that of RNA or DNA in growing Saccharomyces cerevisiae cells. Polypeptide biosynthesis in a cell-free system from the yeast was refractory to the antibiotic, suggesting the possibility that the biosynthesis of one or more amino acids might be inhibited. Intracellular amino acid pools, particularly those of methionine, isoleucine and threonine were significantly reduced when yeast cells were incubated in the presence of RI-331. Consistent with this, the growth-inhibitory activity of RI-331 was markedly reversed by the addition of these amino acids into the growth medium, and an even greater effect was exerted by homoserine which works as a common metabolic precursor for these amino acids in yeasts. It looks likely therefore that the inhibition of biosyntheses of some or all of these amino acids by RI-331 is primarily responsible for overall inhibition of protein biosynthesis in yeasts, ultimately leading to cytostasis. This possible mechanism of RI-331 action appears to explain favorably the selective toxicity of the antibiotic against yeasts, since mammalians lack enzymatic systems for synthesizing methionine, isoleucine and threonine which are required as essential amino acids for growth.

Amino Acids↗

PubMed1990

[Comparisons of effects of vitamin D3 metabolites on mineralization: utilization of incisor dentin in parathyroidectomized rats].

The rat incisor is continuously growing throughout the animal's life recording the state of mineralization within its dentin at all times. Therefore, it was assumed that the incisor dentin was suitable material for studying the effects of various drugs on such mineralization. The present study set out to examine the effects of vitamin D3 metabolites on the remineralization of dentin and the serum calcium level in parathyroidectomized (PTX) rats. Male Wistar rats weighing about 200-250 g were parathyroidectomized. Each rat was given daily 12 g of a synthetic diet containing 0.1% Ca and 0.4% P (normal P) or 0.06% P (P deficient) without vitamin D. Exp. I: Three groups of rats given a normal P diet were orally administered vehicle, 25 (OH) D3 (50 IU/rat) or 1,25 (OH)2D3 (5 IU/rat) for 5 days from the 28th day after PTX, respectively. Exp. II: Two groups of rats given a normal P diet or a P deficient diet were further divided into 4 sub-groups and intramuscularly administered 0, 5,000, 10,000 or 20,000 IU of vitamin D3 on the 9th day after PTX, respectively. The active vitamin D3, 1,25 (OH)2D3 restored the mineralization of the dentin which had been suppressed following PTX, and elevated the serum calcium level to about 9 mg/dl. However, the 25 (OH) D3 neither restored the mineralization of the dentin nor elevated the serum calcium level in the PTX rats. At doses below 1,000 IU, vitamin D3 could not restore the mineralization of the dentin. However, at massive doses above 5,000 IU, the mineralization was restored in proportion to the dose. The serum calcium levels also increased in proportion to the dose. It is assumed that the increase of the serum calcium level was mainly due to the enhancement of calcium absorption from the intestine by vitamin D3. Both remineralization of the incisor dentin and increase of the serum calcium level were more marked in groups of rats given a P deficient diet than in those given a normal P diet. In all cases in the present experiments, the degree of mineralization of the dentin seemed to correspond with the degree of elevation of the serum calcium levels. These results suggest that the remineralization of the dentin in the PTX rats was attributable to the effect of the vitamin D3 metabolites on serum calcium regulation. Relative biological activities of 1,25 (OH)2D3, 25 (OH) D3 and vitamin D3 on the remineralization of dentin were estimated to be 1, less than 0.02 and less than 0.001, respectively.

Animals↗

PubMed1990

Development and clinical application of a portable oxygen concentrator.

We have produced a compact, lightweight oxygen concentrator, using a newly-developed polymer of poly [1-(trimethylsilyl)-1-propyne] with a performance, i.e. oxygen permeability, of 61 x 10 cm3 (STP) cm/cm2 s cmHg, which is 17 times higher than that of the membrane material of conventional concentrators. The oxygen and nitrogen selectivity was 1.80. The dimensions of the apparatus are 325 x 180 x 150 mm and it weighs about 4.0 kg. It is actuated by a battery (DC 12 V, 5.6 Ah), with a 100 V AC source and a car battery (12 V) source also available. The power consumption is 70 W. The generated oxygen concentration is about 30%, and the maximum flow rate is 41/min. Applying 10 samples of various chronic pulmonary diseases to the subject, the suction of oxygen from the apparatus in the patients' rest state was conducted. An increase in the PaO2, from an average of 59.1 Torr before the suction to an average of 68.5 Torr after the suction, together with easing of breathing, was indicated. The usefulness of this apparatus for supplying portable oxygen-treatment to patients with chronic respiratory disease is shown.

Berylliosis↗

PubMed1990

Potentiation of inner ear damage following electron beam irradiation with CDDP administration.

This study was designed to examine the combined ototoxic effects of cisplatin, an antitumor platinum compound, administration and electron beam irradiation on the inner ear of guinea pigs, histopathologically. One group received saline solution 4 ml/kg/day and the other group received cisplatin of 2 mg/4 ml/kg/day for five consecutive days. The right temporal bones of all animals of both groups were exposed to the electron beam of 14 Gy/day 3 hours after the daily injection of saline or cisplatin. All animals were sacrificed for inner ear histopathological findings 21 days after the last injection. A combination of cisplatin administration and electron beam irradiation produced a severe potentiation of the outer hair cell damage with no inner hair cell damage. Therefore, in treatment of head and neck carcinomas, it is important to pay attention to inner ear damage caused by combination therapy of cisplatin and electron beam irradiation which involves the inner ear.

Animals↗

PubMed1990

[Clinical, cytogenetic and immunological studies of 2 cases with B-cell acute lymphocytic leukemia. Comparison between B-ALL and Burkitt's lymphoma reported in Japan].

Two patients with acute lymphocytic leukemia of B-cell phenotype (B-ALL) are described. They were 77-year-old female and 34-year-old male. One patient presented with marked splenomegaly, and the other with rupture of spleen on admission. Leukemic morphology revealed a typical L3 profile by FAB classification system in both cases. Immunologic analysis showed the presence of surface immunoglobulins in both cases, and one phenotype was IgM kappa, whereas the other was IgG kappa. Cytogenetic study revealed the typical translocations (8; 14) in both cases. Following chemotherapy, complete remission was achieved in one case, but the other died 36 days after admission. Including our two cases, we studied 12 cases of B-ALL and 77 cases of Burkitt's lymphoma reported in Japan, investigating the clinical prognosis as well as the biological features. We concluded that there are no significant difference of survival between B-ALL and Burkitt's lymphoma. We estimated it is due to oncogenesis from the same original cell in despite of the difference in main tumor site between two diseases.

Adult↗

PubMed1990

A case of GM1-gangliosidosis type I: glycosphingolipid profiles of urine and transformed lymphocytes and beta-D-galactosidase activities in peripheral lymphocytes, cultured skin fibroblasts and transformed lymphocytes.

A female infant with early-onset GM1-gangliosidosis type I was investigated. The lymphocytes, transformed lymphocytes and cultured skin fibroblasts of the patient were demonstrated to have severe beta-D-galactosidase deficiency. The beta-D-galactosidase activities of these cells from the patient's father and mother were at the lower limit of the normal range. The oligosaccharide accumulation in urine of the patient showed the typical type I GM1-gangliosidosis pattern, but no GM1 ganglioside was detected in the patient's urine or transformed lymphocytes. The clinical features were compatible with infantile GM1-gangliosidosis. The mixture of homogenates from the cultured fibroblasts or transformed lymphocytes of the patient and controls showed no complementation of beta-D-galactosidase activity against the controls.

Cells, Cultured↗

PubMed1990

[Effects of 1,25-dihydroxyvitamin D3 on mineralization of incisor dentin in parathyroidectomized rats].

Male Wistar rats (8 weeks old) were parathyroidectomized (PTX) and given daily subcutaneous injections of different doses (0, 25, 50 or 100 ng/kg) of 1,25 (OH)2D3 for 13 days. Changes in plasma calcium and phosphorus levels were monitored at 3 day intervals. An appositional rate of dentin was estimated by a time marking method; that is, the distance of two lead lines deposited in a transverse section of the incisor dentin on the 9th and 12th days of the experimental period was measured. The plasma calcium levels that had been lowered by PTX were elevated dose-dependently following injections of the drug, but the plasma phosphorus levels that had been elevated by PTX were lowered. The body weight was not affected by the administration of the drug. However, the values for the dry weight and ash weight, and the calcium and phosphorus contents of the upper incisors increased dose-dependently. The mineralization of the dentin, that had been suppressed by PTX, also recovered dose-dependently. Apposition rates of the dentin in groups of rats given various doses of the drug (25, 50 and 100 ng/kg/day) averaged 46, 61 and 69 microns/3 days respectively. There was a significant correlation between the apposition rate of the dentin and the plasma calcium level. The correlation coefficients were estimated to be 0.956 (y = 17.2 + 4.6 chi, p less than 0.001) on the lingual aspect and 0.941 (y = 11.4 + 5.3 chi, p less than 0.001) on the labial aspect. However, the values for the mineralization of incisor dentin were inversely proportional to the plasma phosphorus levels. These results indicate that the stimulating effect of 1,25 (OH)2D3 on the mineralization of the dentin in PTX rats is primarily dependent upon the increase in plasma calcium levels by the hormone. The direct effect of 1,25 (OH)2D3 on the mineralization of dentin could not be demonstrated in this experiment.

Animals↗

PubMed1990

[Clinical study on the treatment of hypersensitive dentin by GaAlAs laser diode using the double blind test].

This study was conducted to evaluate the results of treating hypersensitive dentin with a GaAlAs semiconductor laser diode using the double blind test. For this purpose, sixty-seven teeth were examined. Thirty of the teeth were treated with laser irradiation (active group), while the other 36 were not (dummy group). The irradiation equipment was obtained from J. Morita Co. and operated at a continuous wavelength of 790 nm and a laser strength of 30 mW. The following results were obtained: After two hours of laser irradiation, 40% of the active group and 13.9% of the dummy group showed effective results. After one day, these values were 36.9% and 13.9%, and after 5 days, 43.3% and 19.4%, respectively. A overall evaluation indicated these values to be 60.0% and 22.2%, respectively. In evaluating these four results, significant differences are apparent between the active and dummy groups. The present results indicate that laser irradiation may possibly be effective in decreasing pain when treating hypersensitive dentin.

Dentin Sensitivity↗

PubMed1990

Hepatic resection for advanced hepatocellular carcinoma with removal of portal vein tumor thrombi.

In 13 of 398 patients who underwent hepatectomy, tumor thrombi of the remnant portal vein was concomitantly removed by the balloon catheter method in 8, an open method under hepatic vascular exclusion in 1, and resection of the occlusive portal segment followed by portal reconstruction in 4. In 8 of these patients the liver was cirrhotic. The mode of hepatectomy consisted of bisegmetectomy or trisegmentectomy in 11, segmentectomy in one, and partial resection in one patient. Two patients died of portal thrombosis or hepatic failure in the hospital. The mean survival in four patients was 12 months. Seven are still alive (mean, 16 months). In the corresponding period, nine patients with occlusive tumor thrombi of the portal confluence were hospitalized without operation and survived up to 4 months (mean, 64 days) after detection of the tumoral occlusion. The causes of death of the nine patients were bleeding esophageal varices, rupture of the tumor, or hepatic failure. It was revealed that removal of tumor thrombi in the remnant portal vein contributes to (1) portal decompression, (2) feasibility of arterial embolization, and (3) increase in resectability of the main tumor. At present, this procedure might be regarded as an emergency procedure for the avoidance of the above lethal impendence, but it may open the door to an adjuvant therapy.

Aged↗

PubMed1990

[Granular lymphocyte proliferative disorder with penis cancer].

A case of granular lymphocyte proliferative disorder with squamous cell carcinoma of penis is described. A 77-year-old Japanese male was admitted to our hospital in March, 1989 because of ulceration of penis and lymphocytosis. He had hepatomegaly and lymphadenopathy but not splenomegaly on physical examination. The WBC count was 10800/microliters with 83% of granular lymphocytes. Thrombocytopenia (32000/microliters) and mild anemia were also demonstrated. Bone marrow aspirate showed hypercellular marrow with 84% of granular lymphocytes. Proliferative granular lymphocytes were CD2+ CD3+ CD4- CD8- CDw29+ and exhibited ADCC activity but not NK activity. On March 15, amputation of penis was performed. But his lymphocytosis didn't change and thrombocytopenia increased. Thus we considered his granular lymphocytosis was neoplastic rather than reactive. Our case seemed to be rare and was compared with previous reports.

Aged↗

PubMed1990

[Malignant lymphoma with acute renal failure and nephrotic syndrome].

A case of non-Hodgkin's lymphoma with nephrotic syndrome and acute renal failure is described. A 60-year-old Japanese male was admitted to our hospital in November, 1988, because of lymphadenopathy, fever, night sweat, weight loss. On physical examination, lymphadenopathy was present in both cervical, submandibular, supraclavicular, axillary and inguinal regions. The leukocyte count was 9,700/microliters with 85% neutrophils and 2% atypical lymphocytes. Renal function was normal. Lymph node biopsy showed non-Hodgkin's lymphoma of diffuse, large cell type. Immunohistologic examination showed T cell type. A few days later, he fell into acute renal failure. After systemic chemotherapy, he showed prompt improvement in renal function. Echo and computerized tomography (CT) of abdomen revealed no compression of the ureters and bladder. Renal biopsy findings suggested mesangium proliferative glomerulonephritis without invasion of tumor cells. Our case seemed to be rare and was compared with previous reports.

Acute Kidney Injury↗

PubMed1990

Adult Still's disease: a multicenter survey of Japanese patients.

A comprehensive survey of Japanese patients with adult Still's disease was made by questionnaire which was sent to major institutions with rheumatology units in Japan. Of 146 cases from 32 institutions, 90 were judged to be definitely diagnosed as adult Still's disease. The major clinical features in these 90 patients consisted of high fever, polyarthralgia, rash, increased erythrocyte sedimentation rate, negative autoantibodies, leukocytosis, liver dysfunction, and hyperferritinemia. The incidence of several features showed significant differences between these cases and previous nonJapanese cases.

Adolescent↗

PubMed1990

[Two cases of budgerigar breeder's lung].

We report 2 patients with Bird breeder's lung associated with keeping budgerigars. Patient 1 kept a budgerigar indoors for 13 years. Histological examination revealed fibrosis and granulomatous changes in the alveolar septa. Among T lymphocyte subsets in BALF, helper T cell were increased. In the serum, precipitating antibodies to budgerigar dropping extract were observed. Patient 2 had kept Budgerigar for 7 months. Histologically, alveolitis was the primary finding, and suppressor T cell in the BALF were increased. Precipitating antibodies to budgerigar dropping extract was observed only in the BALF but not in serum. In patient 1 who showed a chronic course and granuloma formation, helper T cell in the BALF were increased while in patient 2 who showed an acute course and alveolitis, suppressor T cell in the BALF were increased, and precipitating antibody was observed only in the BALF. These findings suggest that T lymphocyte subsets in the BALF differ depending on the stage of hypersensitivity pneumonitis, and specific local antibody production precedes systemic antibody production.

Antibody Formation↗

PubMed1990

[Mitral valve replacement in 12-month-old infant with parachute mitral valve associated with ventricular and coronary sinus septal defect].

A 12-month-old infant, weighting 6.7 kg, underwent mitral valve replacement with a 17 mm Björk-Shiley prosthetic valve for parachute mitral valve, and patch closure of the associated ventricular and coronary sinus septal defects. Progressive pulmonary artery hypertension and heart failure required surgical intervention. The diagnosis of parachute mitral valve and associated lesions was established by echocardiogram and angiogram. Postoperative recovery was uneventful and he is doing well 3 years after the operation. To our knowledge this is the first successful case to be reported in the literature with such combination of the congenital anomalies.

Age Factors↗